That guy on TV is a broker. He doesn't want to hold any gold. He wants to sell and buy at the same time and make money off of the spread.
A market maker is the guy who's tying to capture the spread, but they don't really go around trying to get the public to buy and sell.
Any vendor will buy a good at say, $9 and sell at $10. In the US there are many pawn shops saying "We buy and sell gold!" - it's never at the same price.
#1: A smart gold trader will buy low, sell high.. they will buy more gold when prices are low and advertise to sell more when the price is high.
Brokering fees are not calculated in with the base prices, though it would be once it's time to calculate returns.